Decoding Clues to Alzheimer's Disease

June 24, 2014

by Jennifer Anderson

For Yakeel T. Quiroz, finding a cure for Alzheimer’s disease is more than a career and quest for knowledge.

“Once you get to work with families affected by Alzheimer’s disease, get to know them, it’s hard to leave them,” says Quiroz, a clinical/research fellow in neuropsychology at Massachusetts General Hospital/Harvard Medical School in Boston.

The 5,000-plus clan in Medellin, Colombia, and nearby remote mountain villages is the world’s largest known family to experience Alzheimer’s. Their strain of the disease is early onset, with symptoms often surfacing in the mid-40s. About half the family has the disease.

Quiroz’s mentor, Medellin neurologist Francisco Lopera, MD, identified the disease three decades ago as an altered protein on the presenilin 1 gene on chromosome 14—the “Paisa mutation.” When someone has the mutation, Alzheimer’s is guaranteed. By comparison, the gene associated with the more common, sporadic Alzheimer’s afflicting the elderly, merely places the carrier at risk.

Quiroz explains that once there is clinical presentation, and dementia sets in, the progression of familial Alzheimer’s is similar to that of the sporadic. Understanding the familial, she explains, may offer clues for treating both types of Alzheimer’s. “We’re trying to get a better sense of what’s going on in the pre-clinical phase,” she says.

For her dissertation, Quiroz studied MRI scans of the brains of family members who were 25 and older and had no symptoms. Through imaging and other techniques, she learned the brain activity of those carrying the Paisa mutation were different than the brains of people without the mutation. “Their brains were functioning as if they already had the Alzheimer’s pathology,” she said.

Quiroz then went to 18- to 25-year-olds and found similar differences—approximately 20 years before symptoms would set in. Now, she is studying the brain scans of children as young as nine to look for similar changes.

Quiroz wants to identify the earliest pre-clinical markers of Alzheimer’s disease as part of an international collaboration that involves the Alzheimer’s Prevention Initiative in Phoenix, AZ and the University of Antioquia in Colombia.

Quiroz has been working with Lopera since her undergraduate years in the late 1990s at the University of Antioquia. She traveled to Colombia several times to collect data for her dissertation for Boston University, and she continues to travel to Colombia twice a year as part of her ongoing studies with the Alzheimer’s Prevention Initiative.

“I meet these people when they are fine,” she says. “At some point they no longer recognize me. There is no hope for them. You want to do anything you can to help them, but at some point there is nothing you can do.”

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Yakeel Quiroz was recently honored with the Federation of Associations in Behavioral & Brain Sciences (FABBS) Foundation Early Career Impact Award during the Massachusetts Neuropsychological Society meeting in Boston, Massachusetts.